mm to meters cube - Conversion question

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mm to meters cube - Conversion question

by MFaulkner » Sat May 15, 2010 10:35 am
I apologize for not having an official answer for this as I'm pulling this problem off my memory from the actual exam. The numbers were probably different, but I'm confident question type and answer is essential the same.

If the volume of a box is 1,463,000 cubic millimeters, then what is the volume of the box in cubic meters? (.001 m = 1mm)

I set up two ratios and cross multiplied:

x meters/1,463,000mm = .001 meters/1mm

= 1,463 meters

HOWEVER, there was no answer choice with 1,463. The answer choices were similar as to what follows :
a.) 14.63
b.) 1.463
c.) .1463
d) .01463
e.) .001463

When using an online conversion calculator to go from mm cubed to m cube I obtain the answer (E) .001463

Anyone know what I did wrong here? Does the fact that it's going from mm-cubed to meters-cube require some extra step?? I spent an abnormal amount of time on this question when I consider these types of questions to be lower level/easy.

Thank you,
Michael

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by Gmat_War » Sat May 15, 2010 11:25 am
Given 0.001 m=1 mm
Therefore 1 /1000 m=1 mm
=> (1/1000)^3 m^3 =1 mm^3
=>1/(10^9) m^3=1 mm^3

Apply this in the volume of the box given
1463000/(10^9) m^3=1463/(10^6) and this gives the answer E

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by orel » Sat May 15, 2010 11:35 am
Hi Mfaulkner,

Here we need to find the volume in cubic meters.

The answer to this question lies in the question itself:

0.001m=1mm. if we cube both sides of this equation, we will have:

(0.001m)^3=(1mm)^3 =>>> 0.000000001m^3=1mm^3

Now we can replace mm^3 with m^3:

1,463,000 mm^3= 1463000*0.000000001m^3= 0.001463m^3

Hence, the correct answer is E.

best,
orel

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by MFaulkner » Sat May 15, 2010 11:46 am
ahh!!

I can't believe I didn't catch that!

Another easy problem disguised with the addition one stupid word!

Thank you both for the explanation